[mythtv-users] Nvidia 260 yuv gives better image quality

Andre mythtv-list at dinkum.org.uk
Mon Nov 8 15:35:41 UTC 2010


I recently upgraded my frontend to mythbuntu 10.10 to get GT220 HDMi audio working (upgraded alsa on 10.04 was giving grief) and as a consequence got Nvidia 260.19.06.

Big improvement for me, Nvidia settings now has an RGB/YUV setting and this is resolved a nagging problem I had with vdpau. Previously in shadows and dark scenes there is a colour cast which varies from recording to recording in it's colour and severity, the display (a DLP projector) is calibrated to reduce this but it varies so still shows up some of the time. Set display mode to YUV and immediately shadows are as they should be, detail in shadows is clear and the correct colour :-))

I've flipped this back and forth a few times, calibrated the projector in each mode and consistently in RGB there's a cast, in YUV it's gone. I've been running this for a couple of weeks and it seems to be always good.

Of course as I'm a broadcast engineer I notice these things (can't not notice them actually) and most people probably wouldn't see it or care but I know there are some people on here who care about the finest details so I thought it worth a mention.

It may be that this is a problem specific to my projector (Optoma HD80) as I've seen the same problem when I was using a PS3 to play recordings. Either way it may affect other people's TVs and displays so any improvement is welcome. The only other HDMI device around here is a PC LCD, it's impossible to see such a subtle effect on that.

You need a display or TV capable of accepting YUV over HDMI before this option even becomes available. There's also a restricted range setting for RGB which makes the desktop look much better (and myth themes maybe?) if your display can't (or won't ) do full range RGB.

Incidentally the occasional stutters on big scene changes seem to have gone too, difficult to know what fixed that when everything has changed except the mythtv version, 0.23.1 GT220 1GB, advanced 2x de-int, hq scaling and ivtc btw. 

Andre


More information about the mythtv-users mailing list